Case neck and shoulder separation?

konamtbiker

I know what signs are for case head separation. What are the signs for case neck and shoulder separation. Thanks in advance

jonk

I've only seen one neck rip off. And that went down and out the bore as it wasn't in the chamber after firing. This was on a semi auto French MAS 49/56. No ill effects- though it gives me the willies to think that if that neck had stayed in the chamber the next round likely would have slamfired out of battery. If anything will happen, the neck or shoulder will crack or burn through. I'd say there ARE no signs, and it is very rare. No need to worry about this unless you are having problems with other brass in the batch, at which point neck annealing should solve any problems.

dtknowles

Jonk's comments are very cogent. I saw a report of a blow-up of a CZ-52 that was blamed on a particular batch of imported Com Block Mil Surp ammo 7.62 x 25. The report indicated that others had reported excessive pressures with this ammo. It is my belief that this ammo has neck separations that leave brass in the throat of the chamber that obstructs the bullet when the next round is fired. This is a hard to detect failure that can be catastrophic. I always like to look at spent cases of any reloads or suspect ammo for clues of any potential failure modes. Split necks on factory or arsenal ammo is very suspect, could be badly aged brass.

Tim